Love the tags

As another poster pointed out, when you hear about objects below 0 Kelvin, a different definition of temperature than what you're used to is being used. For all temperatures that fall within human intuition (and a great deal of those beyond intuition) as temperature goes up or down, entropy follows suit. This is defining entropy by temperature. We could instead define temperature by entropy. In doing so, as entropy goes up and down, temperature goes up and down. For the most part. At super crazy high, big bang like temperatures, entropy starts to *decrease*. Under the temperature defined by entropy model, this is interpreted as negative kelvin (since that's the only way our math meshes with the temperature defined by entropy model).